Data loss prevention (DLP) is a set of policies and tools that aim to prevent unauthorized disclosure of sensitive data. DLP transport rules are rules that apply to email messages that are sent or received by an organization's mail server. These rules can provide deep content analysis, which means they can scan the content of email messages and attachments for sensitive data patterns, such as client lists or contact information. If a rule detects a violation of the DLP policy, it can take actions such as blocking, quarantining, or notifying the sender or recipient. This would improve security and help prevent sales team members from sending sensitive client lists to their personal accounts. Reference: CompTIA Cybersecurity Analyst (CySA+) Certification Exam Objectives (CS0-002), page 14; https://docs.microsoft.com/en-us/exchange/security-and-compliance/mail-flow-rules/data-loss-prevention